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Guest Message by DevFuse

# 1 = 2 revisited

33 replies to this topic

### #1 bonanova

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Posted 21 January 2013 - 11:35 AM

It is a beginner-level bit of mathematical magic to prove that 1=2.

This demonstration probably occurs multiple times in the history of this forum.
Its fallacy depends on embedding, and cleverly hiding somewhere in the "analysis," a division by zero.
Which of course is not permitted. So regarding this matter our world is still a safe abode.

Nonetheless, this equality still has a life for puzzle solvers.

By the application of a familiar proof, the addition of a single well-known mathematical symbol,
and without resorting to prohibited mathematical operations, 1=2 can still be shown to be true.

Have fun, and please use spoilers.
• 0

Vidi vici veni.

### #2 vistaptb

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Posted 21 January 2013 - 07:22 PM

Spoiler for Here's one

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### #3 phil1882

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Posted 21 January 2013 - 08:17 PM

Spoiler for

• 0

### #4 superprismatic

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Posted 22 January 2013 - 12:52 AM

Spoiler for a solid induction proof

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### #5 bushindo

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Posted 22 January 2013 - 01:00 AM

Spoiler for a solid=solid induction=induction proof'=proof

Counter example to this proof =)
Spoiler for

• 0

### #6 superprismatic

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Posted 22 January 2013 - 01:05 AM

Spoiler for a solid=solid induction=induction proof'=proof

Counter example to this proof =)
Spoiler for

Spoiler for but

• 0

### #7 bonanova

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Posted 22 January 2013 - 09:24 PM

Good thinking so far, but it's not as complicated as it looks.

You'll just have to go a bit more outside the box.

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Vidi vici veni.

### #8 bonanova

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Posted 23 January 2013 - 05:55 AM

Spoiler for Here's one

But not the solution I had in mind.
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Vidi vici veni.

### #9 superprismatic

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Posted 23 January 2013 - 08:33 PM

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### #10 superprismatic

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Posted 23 January 2013 - 09:01 PM